Wall telephone subset



Dec. 19, 1944. s, MCLARN WALL TELEPHONE SUBSET Filed 001;. 30.1942

3 Sheets-Sheet l 'FIGJ.

0 fa y 1 H INVENTOR. 1 kvssr 5. MCZAR/V ATTOME'X Dec. 19, 1944. E. s. McLARN 2,365,481

WALL TELEPHONE SUBSET Filed Oct. 30. 1942 5 Sheets-Sheet 2 ATTORIYEY WALL TELEPHONE SUBSE'I Filed Oct. 50. 1942 3 Sheets-Sheet 3 IN YEN TOR. [791/597 62 Mc ZARA ATTOEAEY.

Patented Dec. 19, 1944 UNITED STATES PATENT OF FlCE 2,365,481 g WALL TELEPHONE sIJBsn'r Ernest S McLarn, ,Manhasset, N. .Y.,'assi g-nor to International Standard Electric Corporation, New York, N. Y., a corporationof Delaware Application October 30, 1942.; :Serial No. 453,921

This invention relates toa wall telephone subset. An object of the invention is the provision of a telephone subset of simplified construction which may be assembled and maintained at a minimum cost.

Another object of the invention is to provide a telephone subset in which any of the parts may be removed or replaced without using anytool other than a screw driver.

:Stillanother object, of the invention is the pro- .vision of a telephone instrument which can be manufactured in quantities from pre-tested parts, all of which are secured by screws as the instrument is being assembled, thereby preventing errors in assembling the instrument and e1im-; mating the expense of final tests on the completed instrument.

A further object of the invention is the provision of. a telephone instrument which may be maintained and installed by those having no great mechanical or electrical skill.

A further object of the invention is the provision of a telephone with a removable or hinged cover and having a contact assembly which can be inspected under normal operating conditions with thecover open or removed. 4

A still further object vof the invention is the provision of a telephone subset assembly which may b used with different type covers, so that with one type of cover the assembly is adapted for use as a wall type telephone and with another type cover the same assembly may be used as a desk-type subset.

Other objects of the invention will appear in the following description given with the aid of the accompanying drawings of which Fig. 1 shows in vertical section one embodiment of a wall telephone according to the present invention on a' somewhat enlarged scale for the ,sakeof clearnessj porting P destal on a reduced scale, the section being taken through 4-4 of Fig. 2.;

Fig. ,5 is a view of the interior vof the contact pedestal with the cover and contact assembly re- -moved;;and

Fig. 6 shows the invention as applied to a desk set. Referring to Figures '1 and 2: A flat metal .10, provided with feet ll forms a panel on mounted; "Secured :to panel 10, .nearlthe upper part -thereof is a generally flat sub-panel 12 of molded material. A number of threaded bushings I3, Fig. 5, having soldering lugs depending below the under surface "of s'ubepanel 12 are positioned in the sub-panel during the -molding process- On the upper suriaceof the sub-panel,

a number of screws .are shown in 2 which screw into the threaded portions of bushings .113.

Of these screws, l5 and I6 fasten the lugs of a condenser unit H, to .preewired circuits under the sub panel. Another screw, not shown passing through an opening in :the opposite end of the condenser and threaded into panel 19 secures the condenser firmly imposition.

Screws l8 .and 19 are used to connect ringer 20 to the sub-panel circuits. Two other screws 21, Fig. l, ar used to attach the ringer to panel 10.

Screws 125, 2B and 21, 218 connect an induction coil unit 29 to the sub-panel circuits. Another screw, not'shown is used to secure the opposite end of the induction coil unit to panel 1H].

Screws '31, '32, 313, .34 are used to :connect the terminals of a four wire :cab'le, not shown, extending from the dial mechanism, 1, to the subpanel circuits, while screw .35 and the clippzfi held thereby are used tdsupport the cable.

Screws 40,111,162 and 43, .M, 4.5, are used for connecting telephone cords to the sub-panel. These cords may be of the tipped type in which case the screws are used :to fasten the cord tips to the set, or they may he used to connect the sol-called tipless cords and in this case the screws are .used to support :a clamping block, not shown, rovided with teeth which penetrate the insulation and make contact with th respective conductors of .a parallel conductor cord. This arrangement is disclosed :in .applicants application Serial Number $150,027, .filed July 57, 1 942.

Underneath sub-panel 1-2, the soldering lugs 14 depending from threaded bushings are interconnected :by suitable conductors in the desired manner before the subepanel is fastened to panel ill. Screwslilland fill .areused to attachthesubpanel to .panel 51:0.

At the lower central portion of the sub-panel l2, 2. generally hollow column or pedestal 52 is molded, which projectssubstantially perpendicularly from the flat portion of the sub-panel. The pedestal is slightlytapered. In Fig. 2, reference character 53 designates the line marking the respectively, Fig. 5, in the pedestal.

the top of the pedestal which has a generally oblong-shaped outline.

Looking at the to and left sides of the pedestal, as shown in Fig. 2, these sides are completely closed by the molded material, while the lower side is entirely open and a portion of the right side is open extending downward from the bead 55 formed on the right side of the column perpendicular to the base. These open portions of the pedestal permit the installation and observation of the operation of cradle contacts described further on, in the interior of the pedestal.

The left side of the pedestal, as shown in Fig. 2 is provided with a raised bead 56 similar to 55 and in the same plane therewith. These beads are used to support a cover 51 of thin sheet metal provided with ridges 58 complementary to said beads and adapted to be snapped or sprung hereover. Cover 57 when in place completely encloses the open parts of the pedestal just described and dotted lines inFig. 2.

In Fig. 4 the pedestal isshown in section taken through the middle thereof looking from the left of Fig. 2 toward the right side of the drawings. This figure shows how the front and also the lower part of the right side of the pedestal is open below bead 55.

A group of cradle contacts 69 Fig. 1, in an insulating mounting 6| are secured by screws 62 to a metal stamping 63 which in turn is fastened to a thickened portion 65 of the interior of the pedestal by screws 66 which extend entirely through the pedestal via screw holes 61, Fig, 5, and are secured by nuts, not shown, on the upper surface of the pedestal. The ovalshaped recess, 63, Fig. is to provideclearance for the ends of screws 62. The rear portions 69 ofcontacts 69 extend through an opening in sub-panel I2 where they are connected to desired circuits at the rear of the sub-panel.

One of the contacts 60 is provided with a pair of arms '19 which between them on a suitable spindle support a roller TI. This roller arrangement forms a convenient way for operating the contacts 69 from a cradle plunger 12 which enages roller ll whenever the telephone hand set, not shown is, positioned in the cradle. This arrangement will be described further on.

Plunger 12 is formed with a flange 13 and a shoulder M and is free to reciporcate in a hole l5, Fig. 5, in the pedestal and a hole in a metallic bridge 16 secured to the pedestal by screws 11 and 18 which pass through holes 19 and 80, Spring 85 tends to hold flange 13 against the under surface of the bridge and holds the plunger 12 out of contact with roller 7| when the hand set is removed from thecradle causing these parts to assume the position shown in the drawings.

The section of plunger 12, beyond bridge 19 extends through a member 90 of novel use and construction which forms part of the outer case or enclosure of the subset instrument. Member 99 will be referred to again further on in the description.

The cover 9|, Figs. 1 and 3, may have any suitable contour. In the present embodiment of the invention a cover is shown having pleasing symmetrical lines. Looking directly at the instrument, the cover has a generally oblong outline suggested by a section 92 extendingoutward approximately perpendicular to the edge of panel HI, and forming part of the side portions of the cover. At the lower part of the cover, set-back section 93 is formed which tapers inwardly on three sides at 94 toward a front portion 95 in which an opening 96 is formed for dial mechanism 91.

The dial mechanism is detachably secured by screws98, one of which is shown in Fig. 1 which are accessible from the interior of the cover. In the present embodiment the preferred form of dial mechanism is provided with a transparent casing through which the operation of the dial mechanism can be observed from the rear. Reference character 99, Fig. 1 indicates a transparent cover for a dial mechanism havin such a transparent case. Cover 99 secured to cover 9| by screws M32, is provided with a turned over edge I99 which overlaps an annular ridge |9| formed on the inside of cover 9| to aid in excluding dust and moisture from the under surface of the dial mechanism, while the upper surface of the dial mechanism is similarly protected by annular gasket I03 disposed between the outer part of the dial mechanism andthe outer surface of cover 9|.

As previously stated, the dial mechanism of the present embodiment is provided with a fourwire flexible cable, not shown, having terminals which connect to the sub-panel circuits by screws 3|, 32, 33 and 34, Fig. 2. It will be clear from the above description that dial mechanisms be interchanged quite easily with no tool other than a screw driver.

Alongside the edge of the dial, a thin area. N14 is formed in the cover to provide a knock out hole through which a P. B. X button may be inserted if desired. A post I95 molded on the inner surface of easing 9| may be used asa support .40 for the contacts operated by such P. B. X button.

Cover 9! flares outwardly beyond the area supporting the dial sufficiently to clear the front of pedestal 52 and immediately above this area the mid-section of the cover is formed with a slanting depression I which continues over the top of the cover until the edge thereof meets that of member 90. The cover is formed to fit closely about the curved edges of member 98, and both the cover and member 99 have the same general surface contour so that when the cover is in normal closed position, it is hardly noticeable that the top of the enclosure is formed of two separate members, and 9|.

The edge of member 90 is provided with a flange ||2 which fits closely into a recess 3 formed in the under surface of cover 9|, best shown in Figs. 1 and 2, which arrangement generally strengthens the enclosure and aids in exeluding dust.

I Member 99 preferably is detachably secured to panel I9 by means of screw H4, and is provided with a portion H5 which overlaps the edge of panel ID as does the portion I I6, Fig. 1 of cover 9 Rising somewhat above the depressed central portion at the top of cover 9| and on opposite sides thereof is a cradle for a handset formed by projections I29 and |2| on the right top part of the cover and similar portions I22 and I23 on the left top part as shown in Figs. 1 and 3. When a hand-set, not shown is resting in the cradle, plunger 12 will be depressed thereby, reversing the position of contacts 59 from that shown in the drawings.

Cover 9| may be fastened by any suitable means to panel Hi. In the present embodiment the casing is hing edto panel I10 by a simple arrangement consisting of a pair of metal strips I25, one of which is shown in Fig.2 secured by screws, not shown, to bosses formed on the inside surface of casing 91. Apair of spaced'slots I26, one of which is shown in Fig. :2 are provided in panel Ill to receive the respective metal strips I25 which are bent back toward the adjacent edge of panel Ill sufiiciently to hold the strips in the slot. Near the opposite :edge of panel It a slot, not shown, may be provided to receive any simple, catch device which will .be effective to hold "the cover securely in closed position. With the arrangement just described all parts including cover ill of the wall telephone subset may be removed or replaced withno tool other than a screwdriver, and cover 91 maybe easily opened and the parts therein including It is not thought necessary toidescribe the desk set shown in Figure 6 in detail as the parts are similar to those of'the wall set already described and-can be identified fromthe description already iven.

Cover I242 iofthe desk set may be secured to panel I by screws I52 and bushings I53, or by contacts Gil may be freely inspected 'wh'ilet'he telephone is in operating condition.

The arrangement possesses the important advantage that it may be readily converted from .a wall set into a desk set with a few changes other than substituting a desk type cover for the wall type. This feature is important because a telephone plant department may keep on hand a number of dials and panel assemblies sufficient to meet anticipated requirements which may be for either wall telephones or desk sets. Plastic covers of the kind just described are relatively cheap, costing in quantities, less than fifty cents each, and a considerable number of each kind may be kept in stock at small expense and installed on the panel equipment just described according to requirements.

The wall set just described may be converted into a desk set by removing the wall. type cover 91 and member 90. Referring now to Fig. 6: Plunger I2, bridge I6 and spring 85 are removed and the opening I5 in pedestal 52 for plunger I2 may be closed by suitable means, such as disc I30 secured to pedestal 52 by the same screws TI and I8 which formerly held the bridge.

Referring to Fig. 4 it will be noted that a central opening I 3I-I32 is formed in pedestal 52 which extends entirely through the pedestal. When used as a wall telephone opening I3I is closed by a pair of disc-shaped members I33 and I34 held together on opposite surfaces of Wash ing I35 by screw I36 Fig. l, to exclude dust and moisture from the interior of the pedestal. In converting the wall type telephone to a desk set these discs and the associated screw are removed and a plunger I31 Fig. 6, is inserted in opening I3I-I32 where it is free to reciprocate in bushings I35 and I21. A washer I38 fastened to one end of the plunger by screw I35 limits the upward movement of the plunger due to spring I40 disposed on the plunger between flange MI and the bottom surface of pedestal 52. v

The plunger extends upward through desk type cover I42 and terminates in one button I43 or two buttons suitably spaced disposed within a handset cradle formed by projections I44, I45 and I46, I41, When a handset rests in the cradle, button I43 is depressed and cam surface I48 on plunger I31 engages and moves roller II toward the right of the drawing reversing the position of the contacts 60 from that shown. To keep the plunger from turning and thus displacing plunger-cam I48 relative to roller 1 I, plunger I31 is provided with a pair of axially disposed fins I49 which reciprocate in vertical slots I50, Fig. 2, in a substantially annular member I5I formed at the top of pedestal 52.

the hinged arrangement .describediabove in connection with the wall set. In the, case of the desk set, the bottom of the set is always accessible for removing screws 452 while the hinged arrangement is usually more desirablein a wall set since panel II) is invariably secured to a wall.

What claimed is:

l. A well telephone instrument comprising a panel adapted to be secured to a wall, a cover therefor having a cradle for a'hand set for-med thereon, a recess formed in said cover in the area of said cradle, a member secured to said panel, said member having a flanged edge adapted-to fit into said 'recess, an opening'in saidmemher, a cradle plungerextending from the'interior of said .instrument through said opening adapted to be depressed when engaged by a hand set placed in said cradle.

2. A wall telephone instrument according to claim 1, in which said cover is removable and in which said cradle plunger remains in normal operating position with the cover removed.

3. A wall telephone instrument comprising a panel adapted to be secured to a wall, a member supported by said panel so as to project outwardly therefrom, said member having an opening therein and a fiange at one of its edges, a cradle plunger extending from the interior of the instrument outwardly toward the exterior thereof through said opening, a cover for said instrument having an opening extending from an edge thereof through which said cradle plunger projects whereby said cover may be removed to permit inspection of the interior of the instrument under normal operating conditions, said edge of the cover having a recess adapted to receive the flange of said member.

4. A wall telephone instrument comprising a panel adapted to be secured to a wall, a member projecting outwardly from said panel and secured thereto provided with an opening, a cradle plunger extending from the interior of said instrument outwardly to the exterior thereof through said opening, a cover for said instrument having an edge portion provided with a recess shaped to fit around at least a part of said member where said member cooperates with said cover in forming an enclosure for said instrument.

5. A wall telephone according to claim 4 in which said cover is hinged whereby the cover may be swung open without disturbing said memher or the cradle plunger extending therethrough.

6. A wall telephone according to claim 4 in which said member is ofa generally fiat shape and formed with a contour similar to th adjacent portions of said cover and forms a part of the enclosure for said instrument when the cover is in closed position.

7. A wall telephone according to claim 4 in which said cover is hinged to said panel, and in which said member has a generally fiat surface shaped to conform to that of the adjacent portions of said cover and having curved edges; and in which said recess in said cover is formed to fit closely around said curved edges.

8. A wall telephone according to claim 4 in which said cover is hinged to said panel, and in the curved edges of said member.

9. A telephone subset assembly adapted to be used in connection with wall type and desk type telephones comprising :a panel, a pedestal supported by said panel, a set of cradle contacts supported by said pedestal, an opening in the top of said pedestal for receiving a cradle plunger for operating said contacts when said assembly is used as desk telephone, and an opening in one side of said pedestal to receive a plunger when the assembly is used as a wall-type telephone.

10. A telephone subset assembly according to claim 9 in which a sub-panel of molded material is secured to said panel, said pedestal being formed integrally with said sub-panel, and wherein when said assembly is used as a wall-type telephone, a member provided with a hole is secured to said panel with said hole in register with said opening in one side of said pedestal, said member forming part of an enclosure for said assembly, a portion of the second mentioned plunger extending through said hole whereby said plunger may be operated from the exterior of said member.

11. A telephone subset assembly according to claim 9 in which a sub-panel of molded material i secured to said panel, said pedestal being formed integrally with said sub-panel, and Wherein when said assembly is used as a wall-type telephone, a member provided with a hole is secured to said panel with said hole in register with said opening in one side of said pedestal, said member forming part of the enclosure for said assembly, a portion of the second mentioned plunger extending through said hole to make possible the operation thereof from the exterior of said member, said member being adapted to be removed from said panel when said assembly is changed from a wall type to a desk type set.

ERNEST S. MCLARN. 

